Attachment for printing presses



M y 1929. P. P. HEMBERGER ATTACHMENT-FOR PRINTING PRESSES Filed March 27, 1928 @727? P flzmefyer INVENTOR M %A ATTORNEY,

' with every contact therewith.

Patented May 7 1929,

1 WWW TA AT NT orF -cn PETER P. HEMBERG'ER, OF BERGENFIELD, JERSEY.

ATTACHMENT FOR PRINTING rnnssns.

Application filed March 2?, 1928. Serial No 264,979.

picked up from the fountain by an inking roller which is intermittently rotated. .by any of the well known'mechanisms used for this purpose. The ink is then delivered from the ink fountain roller to an ink plate by means of a doctor roller, which is mounted for oscillatory movement so as to be moved alternately into and out of contact with the fountain roller and inking plate;

Contact of the doctor roller with the inking roller and the inking plate causes the former to rotate, and in its movement between the inking roller and plate, it is necessary that the doctor roller be rotatedso as to bring a new portion of its surface into contact with the inking roller and plate, to effect an even distribution of the ink and to prevent uneven wear of the-doctor. result of this arrangement, the doctor roller is spinning very rapidly when it is out of contact with both the inking roller and plate. a p

For various reasons known to the art, it is desirable to control this free rotation of the doctor, and'it is one of the, objects of this invention to provide .means for controlling the free rotation of the doctor and for insuring the presentationof a new portion of the doctor roller surface to the inking roller I accomplish this object by means of an attachment hereinafter described, set forth in the claims, and illustratively exemplified in the accompanying drawing, in which, Figure 1 is a side elevational view of a printing press including my improved attaclnnent; Figure 2, is adetail top plan view of the press and attachment; and Figure 3 is a perspective view of the bracket and idler pulley for one end of a driving belt and brake strap forming part of the elements of the present invention.

Referring to the drawings, 10 denotes the frame work of the press and 11 the ink fountain arranged at the end of the frame 10. Operating in the open end of the fountain 11 is the usual ink roller 12, which is provided with stud shafts 13 at opposite ends mounted in bearings provided by the end Walls of the fountain 11. A; ratchet wheel. 14 is keyed to one of theshafts 13, outside of the fountain 11 and is operated to rotate the roller 12 by means of a pawl 15 carried by an arm 16 pivotally mounted on the shaft 13 ad jacent the ratchet wheel 14. Rocking movement is imparted to the arm 16 through a rod 17 which is reciprocated in the usual manner by mechanism not shown. A printa ing and ink plate 18; lSIHOUDtQd for horizontal reciprocationwithin the, press and a above the elevation of the frame 10. f-The ink from the fountain roller 12 is distributed on. the plate 18 by a doctor roller 19 which is free to rotate in a pair of swinging supports 20, the latter being disposed to move the doctor roller 19 alternately in contact with the fountain roller 12 and then in the path of the reciprocating ink and printe plate 18. I l i Opposite ends of the doctor roller 19 are provided with stud shafts 21, the shaft 21,

on the same side of the press as that of the ratchet wheel. 14:, being provided with a" double grooved pulley 22. The outside groove of the pulley 22 receives a strap 24 thereover, which is anchored at one end to a bracket 25 attached to the frame 10, and

at the other end to a weight 26 guided for tact of the doctor-19 with the ink roller12.

It will be clear that the strap 24 acts as a brake to retard the frcerotation of the doctor between theplate 18 andink roller 12,

and vice versa. 1 r

I control movement of the doctor roller 19, toinsure thepresentation of a new portion of its surface to the ink roller 12 and ink plate 7 18 each time the doctor rollercontacts therewith, by means of a continuv ous belt 30, which is disposed at onecnd about a grooved pulley 31, keyed to the ink roller s'haft13 between the ratchetwheel 14- and ink fountain wall, and which at its other end is disposed about an idler pulley 32. The

upper strand of thebelt 30in its travel be- I tween the pulleys 31 and 32 is directly in the path of the inside groove of the pulley 22, when the latter moves downwardly with the doctor 19 to contact'with the ink roller 12, as illustrated in dotted lines in Figure 1,.

As a result of the pulley 22 coming into contact with the belt 30, the doctor roller 19 is rotated with the ink fountain roller 12.

In order to provide sufficient give for the belt 30 when the pulley 22 descends and picks up its motion, the pulley 32 is loosely mounted on a pin 33 projecting from a pivoted member 3 1 mounted on a pin disposed in an upright projection of the bracket 35. The member ea is yieldably supported against the pull of the belt 30 by a spring 36, one end thereof being attached to an eye v37 on the member 34: and the other end to a rigid arm 38 projecting from one side of the bracket 25, as clearly illustrated in Figure 3;

My invention operates as follows: The press in operation imparts a longitudinal reciprocating movement to the plate 18 which receives a film of ink from the doctor roller 19. The doctor 19 swings in an arcuate path from the ink roller 12 to a position directly in the path of the ink surface of the plate 18, which as just stated receives its supply of ink from the doctor. This position illustratively exemplified in Figure 1. The doctor 19 in its uppermost position has drawn the strap 24 taut and lifted the weight 26. As a consequence when the plate 18 is withdrawn and the doctor 19 is free, the latter is prevented from revolving freely by the braking action of the strap 24. The doctor then moves to its lower position as shown in dotted lines in Figure 1, and just short of the point when it contacts with the surface of the ink roller 12, the weight abuts the stop 29 and frees the doctor for rotation. Simultaneously with the doctor 19 contacting with the ink roller, the ratchet 1a is rotated and with it the inking roller 12, and belt 30. t

The pulley 22 of the doctor 19, having engaged the belt 30, while the doctor and inking rollers move into contact, revolves with the movement of the belt 30. This is very desirable where some difiiculty has been experienced in attempting to rotate the doctor roller from mere contact with the fountain roller, especially'when running very thin inks or gold ink. The doctor roller 19, after receiving a supply of ink from the inking roller 12 is again lifted and during the interval when the doctor is free of the ink roller and the strap brake 24 is still loose over the pulley 22, the doctor roller rotates freely, thereby changing its surface position with respect to the surface of the plate 18 and as a consequence eliminating wear on the said doctor roller 19.

Having now described my invention and the manner in which the same operates, what I claim and desire to secure by Letters Patout is:

1. In combination with the ink fountain roller and doctor roller of a printing press, means for braking the free rotation of the doctor roller during part of its travel, and means for rotating the doctor roller from the fountain roller when released from the braking force.

2. In combination with an ink fountain roller and oscillating doctor roller of a printing press, of a reciprocating ink plate to which the doctor delivers ink from the fountain roller, means cooperating with the doctor roller to prevent free rotation thereof in its travel from the ink plate to a point short of contact with the ink roller, and means operated by the ink roller and in the path of movement of the doctor roller to rotate the latter when it is free and adjacent the ink roller.

3. In combination with an ink fountain roller and doctor roller delivering ink from the ink roller to an ink plate, a pulley for the doctor roller, a strap fixed at one end, and disposed over the doctor roller pulley, a weight for the free end of the strap, and a stop for the weight, whereby the latter will' permit a slack in the strap as the doctorapproaches the ink roller.

4. In combination with an intermittently rotated ink fountain roller, and an oscillating doctor-roller delivering ink fromrthe ink roller to an ink plate, a pulley for the doctor roller, a brake strap fixed at one end and disposed over the doctor roller pulley, a weight for the free end of the strap, a stop for holding the weight and permitting slack in the strap over the said pulley, a pulley for the ink roller, a continuous belt for one end of the last named pulley, and a yieldably mounted pulley for the other end of the belt, the latter being disposed in the path of the doctor pulley to impart rotary movement thereto when approaching the ink fountain roller.

In testimony whereof I affix my signature.

PETER P. HEMBERGER. 

